Re: [malware-list] [RFC 0/5] [TALPA] Intro to a linux interface for on access scanning

Greg KH
2008-08-05T17:09:49Z

On Tue, Aug 05, 2008 at 01:21:01PM +0200, Helge Hafting wrote:
> Greg KH wrote:
>>
>>
>> I don't see anything in the list above that make this a requirement that
>> the code to do this be placed within the kernel.
>>
>> What is wrong with doing it in glibc or some other system-wide library
>> (LD_PRELOAD hooks, etc.)?
>>
>
> A linux virus would trivially get around that by doing its own syscalls
> instead of using glibc. (It might still link dynamically to glibc so
> you don't get suspicious, but won' actually use it when doing bad stuff.)

That's fine, then the file is corrupted. It is when the "normal"
program goes to load the file that we want to block and determine if we
have a problem or not in the data.

virus scanners are not a security model in the aspect of SELinux or
SMACK. If they were, they would just use the LSM interface. virus
scanners are interested in blocking "normal" programs from reading
invalid data from disk before acting on it or executing it.

thanks,

greg k-h